<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>
<body>
    <div id="app">
        <currency-input v-model="price"></currency-input>
    </div>
    <script src="../js/vue.js" charset="utf-8"></script>
    <script type="text/javascript">
        Vue.component('currency-input', {
            template: '<span>$ \
                <input ref="input" \
                v-bind:value="value" \
                v-on:input="updateValue($event.target.value)" \
                />\
            </span>',
            props: ['value'],
            methods: {
                updateValue: function (value) {
                    var formattedValue = value
                    .trim()
                    .slice(0,value.indexOf('.') + 3)
                    if(formattedValue !== value) {
                        this.$refs.input.value = formattedValue
                    }

                    this.$emit('input', Number(formattedValue))
                }
            }
        })

        var vm = new Vue({
            el: '#app'
        })
    </script>
</body>
</html>
